Winter storms off the Oregon and Washington coastlines are expected to bring a new wave of debris from the 2011 tsunami in Japan. Scientists say objects are already washing ashore – with potentially invasive organisms riding along.

In March, 2011 an earthquake and tsunami devastated a large swath of eastern Japan. The tsunami reached heights of over 100 feet in some places, washing large quantities of manmade materials out to sea. Japanese officials estimate that about 1.5 million tons of debris floated out into the Pacific.

Oregon State University marine scientist John Chapman questions the accuracy of that number, but says current tallies of what’s washed ashore on the U.S. West Coast are much lower than that.

“If we look at the amount of debris that we’ve found on the shore. And we try to estimate the poundage of debris and add it all up, it’s not even close,” he said. “So, where is it?”

Chapman says it very well could still be out in the ocean, waiting on the right combination of currents, winds and other factors to bring it ashore in the Pacific Northwest.

So far the tsunami debris has come over in waves. It started with buoys, polystyrene foam and two massive floating docks. The next winter, it was building materials, like lumber. Last winter, a parade of small boats started washing up.

And now the first large object of the season – a 4-by-5 foot shipping tote – has washed up near Oregon’s Seal Rock.

The common feature of all these items is the presence of coastal marine organisms that hitched a ride over from Asia.

He said open oceans are the marine equivalent of deserts: there’s nothing out there. At least, nothing of substance, nutrient-wise that coastal organisms would need to survive. This was the prevailing thought among marine scientists – until that first Japanese dock section washed up in June, 2012 on the Oregon Coast.

“That was the first time that anyone ever considered that marine organisms could drift across the ocean. It wasn’t as if they didn’t think about it, we assumed that it wasn’t possible,” he said.

As the years passed and the debris continued to circulate in the North Pacific, Chapman assumed the amount of living coastal organism would decrease. Again, he’s been proven incorrect.

“We’re still finding species that we haven’t seen before. It doesn’t make sense to us,” he said. “We shouldn’t be doing that, but it seems to be happening.”

The plastic shipping tote that washed up in Oregon in late November was covered in about 200 blue mussels.

Yet, just because non-native marine organisms are washing up on the West Coast doesn’t mean they’re establishing populations here; it doesn’t mean they aren’t, either.

The question is currently being studied by several groups using a variety of methods, from visual surveys to genetic testing.

But the organisms are very tiny and the West Coast is very large. And so far none have been found that can specifically be connected to the tsunami.

“If it was a herd of bison that came across, it would be a no-brainer; we could go out and find it if they got here,” Chapman said.

“But these things aren’t bison. They’re little tiny things – sometimes diseases and parasites. And even if they are here, sometimes we don’t find them for years.”

Despite the challenges facing scientists, Chapman said the waves of tsunami debris present an unprecedented opportunity. Between now and May, he expects to see another round data wash ashore on the coast of the Pacific Northwest.

The Lower Elwha Klallam Tribe is tagging large woody debris to follow it as it moves through the newly restored Elwha River system.

“We’re tracking over 2,000 logs and tree stumps with silver tree tags, from the upstream end of Lake Mills to the river mouth,” said Vivian Leung, a doctoral student of geomorphology at University of Washington.

She’s been working with the tribe since 2012 to study how large wood debris (LWD) has affected the river during and after the removal of the river’s two-fish blocking dams.

“Not only did the dams completely block the supply of sediment downstream, but they also altered the transportation of large wood,” said Mike McHenry, the tribe’s habitat manager. “Both elements are critical for habitat forming processes not only in the river but in the nearshore. The fate of wood is relevant to the recovery of the river and its aquatic resources, especially salmon.”

Silver tags are attached to log and stumps throughout the Elwha River so scientists can track their movements as the river changes during restoration.

As the dams came down, the lake Aldwell and Mills reservoirs were drained, leaving behind thousands of logs and tree stumps that had been buried under sediment and water for the past century. The natural action of the river is transporting the logs and stumps throughout the new riverbed, changing the dynamics of the river and creating better salmon habitat.

Leung is interested in how logjams form and affect channel patterns, how wood is transported through rivers and how the pools they create provide places for salmon to rest, feed and spawn.

“Surprisingly, there’s still a lot of research to be done to understand how large wood debris interacts with river systems,” she said. “So far we have found that logjams and salmon habitat are forming significantly faster in Aldwell than we expected.”

The large logs and rootwads also are aiding revegetation efforts of the lakebeds. The tribe hired a heavy-lift helicopter recently to relocate 500 unmarked logs around Mills. The logs were moved from the former reservoir pool elevation to terraces along the river’s floodplain.

These logs are expected to help stabilize steep slopes and provide sheltered areas for young plants to survive during planned revegetation efforts in the coming years, McHenry said. During 2014-2015, 100,000 woody plants will be planted into the former Mills reservoir surface.

It’s been exactly three years since a huge tsunami in March 2011 took thousands of lives in Japan and washed whole villages out to sea.

Suspected tsunami debris started arriving on our shores the following December, but it’s been less than feared.

Nir Barnea, the federal coordinator for marine debris in the Pacific Northwest, says we may never know for sure where the majority of the tsunami debris went.

“A lot of the debris was made of wood. If you look at the photos from early after the tsunami, you see a lot of wood out there. Some of it — maybe even most of it — has sunk. Other debris may not have reached us. It has dispersed and may never reach us.”

Barnea is awaiting confirmation from the Japanese consulate whether a derelict skiff that washed ashore near Westport, Washington in January can be traced to the 2011 tsunami.

One other skiff with Japanese writing on it was found on the British Columbia coast this winter.

The Oregon Emergency Management division and governor’s office are currently considering whether to shut down the Oregon Joint Tsunami Debris Task Force because it’s no longer needed. Washington shut down its marine debris hotline at the new year because so few people were calling.

If you find something on the beach that looks like tsunami debris, you can still report it by email to: DisasterDebris@noaa.gov.